Method of asembling a DC solenoid with a thermistor

Abstract

Method of assembling a DC solenoid comprising: a coil; a thermistor connected in series to the coil and having a positive temperature coefficient; a pressure-resistant case for housing the thermistor; and a synthetic resin material for sealing the pressure-resistant case and the coil integrally.

I claim: 
     
       1. Method of assembling a DC solenoid with a thermistor, the steps comprising: connecting a thermistor having positive temperature coefficient in series with a coil;   housing the thermistor in a case that is sufficiently resistant to pressure to substantially prevent damage to the thermistor on encapsulation of the case by injection molding material thereabout; and   injection-molding a synthetic resin material to encapsulate and seal the case and the coil integrally while substantially preventing damage to the thermistor by the injection molding process.   
     
     
       2. The method defined in claim 1 wherein the case is made of metal. 
     
     
       3. The method defined in claim 1 wherein the case is made of synthetic resin material. 
     
     
       4. The method defined in claim 1 including: connecting a sub-coil in parallel with the series circuit including the coil and the thermistor; and wherein the injection-molding step encapsulates and integrally seals the sub-coil together with the case of the coil.